Shield for anodes



June 8, 1937.

c. B. COOK, JR

SHIELD FOR ANODES Filed Aug. 8; 1934 Patented June 8, 1937' D ST PATENT OFFICE 3 Claims. My invention relates to the class of devices employed to prevent particles freed from the anode from entering the electrolyte and thereby being deposited upon articles being plated, and 5 an object of my invention, among others, is to provide a shield that shall be particularly eflicient for the purpose for which it is intended and which shall effectually prevent particles freed from an anode from being present in the In the operation of electroplating, unless some means are provided for shielding the anode,

particles will be freed therefrom and will be deposited upon the devices being plated with a result that the plating will be deposited over such particles and the surface will therefore be rough. Various means have been devised for preventing this occurrence but up to the present time, so far as I am aware, no means have been provided which thoroughly and effectually accomplish the result. My improved shield illustrated and described herein eflectually prevents the escape of particles from the anode into the electrolyte and such particles are therefore prevented from being deposited upon the articles being plated, in the accompanying drawing illustrating my'improvement the numeral 6 denoting a tank or vat of a type usuallyemployed in electroplating operations, 5 an electrolyte within said tank, 7 a rod from which an anode d is suspended and 8 a rod from which the articles to be plated are suspended. as shown herein such articles being placed within a tray it suspended from the rod 9. All the parts thus far described and illustrated are of old and well known construction and further and detailed illustration and description are therefore omitted, and theelectric wiring by means of which the electro deposition of metal from the articles to be plated is accomplished are also omitted as they will be readily understood by those skilled in the iart.

55 In carrying out my purpose I provide a shield which has a. layer of paper of such substance or texture that objectionable particles freed from the anode cannot pass through such shield, yet,

at the same time the metal constituting the deposit will' be permitted to pass and be affixed to v5 the articles to be plated.

I have found that a shield composed of paper alone will not answer the purpose for the reason that it is not durable enough ,to withstand handling and the,uses to which it is subjected and 10 I have therefore prepared a protector for the paper. In the structure illustrated herein the shield is constructed in the form of an open-end bag or sack which may be drawn over a plating electrode and immersed in the plating bath. 5 This bag or sack may be closed along the bottom and one side as by means of stitching, the opposite side edge being folded. The paper shield ii is enclosed betwee superposed inner. and

outer protectors I2 and IS in contact therewith, 20 these protectors being preferably composed of some quite closely woven fabric, but they'may consist of any suitable material having suilicient strength to answer the purpose.

In order to prevent an enlargement of the 25 holes in the paper shield caused by the stitching and which is liable to be effected by strains from within the shield, as in insertingthe anodes and in removing them from the shields, the inner protector i2 is stitched as at it along the whole 30 length of the stitched edge, and any strains from within will therefore be resisted by the stitching It and will not be communicated to the stitching i5 which secures both laps of the inner and outer protectors and also of the paper shield together.

The bag or shield may be secured with the anode therein in any suitable manner, as shown herein a tie it having been provided which of course will be located above the surface of the 40 electrolyte.

I have found thatthe paper effectually prevents the escape into the electrolyte oi objectionable particles from the anode, and theinner and outer protectors thoroughly prevent any injury to the paper shield and therefore the device will last indefinitely under ordinary uses to which it is subjected.

In accordance with the-provisions of the patent statutes I have described the principles of operation of my invention, together with the device which I now consider to represent the best embodiment thereof; but I desire to have -it understood that the deviceshown is only illustrative and that the invention may be carried trode and immersed in a plating bathcomprising out by other means and applied to uses other than those above set out.

I claim: I

1. A composite shield for electrodes used in electroplating, said shield comprising an en-" velope of a filtering material, a lining of tougher and more durable material separately stitched alongits edge within said envelope, and an outer covering composed of tough durable material, both said lining and said outer covering being permeable to the electroplating solution, and

said envelope. liningand outer covering all bea 'ing stitched together along the edge to form a bag-like unit.

2. A shield to. be drawn over a plating elec-,

an open-end bag having two piles of cloth and between them a ply of paper permeable to metal ions in the plating bath but impermeable to suspended solids, said plies being secured together in superposed contacting relation.

. '3. A shield to be drawn over a plating electrode and immersed in a plating bath, comprising an open-end bag having inner and outer layers of cloth with an intervening layer of paper which is impermeable to suspended solids in the plating bath but permits the passage of metal ions.

CHARLES B. COOK, JR. 

